RICHTEK RT9801BCE

RT9801
Preliminary
User Programmable Micro-Power Voltage Detectors
General Description
Features
The RT9801 is a micro-power voltage detector
z
User Programmable Threshold 1.5V to 5V in
0.1V Step with ±3% Accuracy
supervising the power supply voltage level for
microprocessors (µP) or digital systems. It provides
z
Low Supply Current 3µ
µA
user programmable threshold levels with 0.1V step
z
Quick Reset within 20µ
µS
ranging from 1.5V to 5V, which covers most digital
z
Built-in Recovery Delay 200mS
applications. It features low supply current of 3µA.
z
Low Functional Supply Voltage 0.9V
Selection of VTH is easily achieved through 3 pins
z
Small SOT-26 Package
connected to GND, VDD or floating for different
threshold voltage settings. Two versions of threshold
Applications
voltages, 1.5V ~ 4V and 2.5V ~ 5V, which are
z
Computers
programmed in factory are offered by customer
z
Controllers
demands.
z
Intelligent Instruments
z
Critical µP and µC Power Monitoring
z
Portable/Battery-Powered Equipment
The RT9801 performs supervisory function by
sending out a reset signal whenever the VDD voltage
falls below a preset threshold level. This reset signal
will last the whole period before VDD recovering.
Reset signal will release after VDD is recovered and
Pin Configurations
Part Number
lasts for the whole period of Reset Active Time-out
RT9801…CE
period.
(Plastic SOT-26)
RT9801
is
N-channel,
open-drain
output
and
provided in SOT-26 package.
Pin Configurations
TOP VIEW
6
5
4
1
2
3
1.
2.
3.
4.
5.
6.
Ordering Information
RT9801… … …
Package Type
E : SOT-26
VSET0
GND
RESET
VDD
VSET2
VSET1
Typical Application Circuit
Operating temperature range
C: Commercial standard
Reset Threshold
A : 2.5V~5V
B : 1.5V~4V
VSET0 VSET1
µP
GND
RT9801
GND
VSET2
VDD
RESET
RESET
VDD
Pull Up
RT9801B V TH = 2.5V in this example
DS9801-00 January 2002
www.richtek-ic.com.tw
1
RT9801
Preliminary
Pin Description
Pin Name
Pin Function
VSET0
Threshold Voltage Selection Pin 1
GND
Ground Pin
RESET
Reset Pulse Output, Negative Pulse
VDD
Power Pin
VSET1
Threshold Voltage Selection Pin 2
VSET2
Threshold Voltage Selection Pin 3
Function Block Diagram
Internal Clock
VDD
VSET0
VSET1
VSET
CMP
TIMER
N
RESET
VSET2
Threshold Voltage Setting
POR
Power On Reset
www.richtek-ic.com.tw
2
DS9801-00 January 2002
RT9801
Preliminary
Absolute Maximum Ratings
z
Terminal Voltage (with Respect to GND)
VDD
-0.3V to 6.0V
All Other Inputs
-0.3V to VDD+0.3V
z
Input Current, VDD
20mA
z
Continuous Power Dissipation, PD @ TA = 25°C
SOT-26
0.25W
z
Operating Junction Temperature Range
-40°C ~ 125°C
z
Storage Temperature Range
-65°C ~ 125°C
z
Package Thermal Resistance
z
SOT-26, θJA
250°C /W
Lead Temperature (Soldering, 5sec.)
260°C
Electrical Characteristics
(VDD = 3.0, unless specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
0.9
--
6
V
Operating VDD (VOUT) Range
VDD
Supply Current
IDD
VDD = 1.5V ~ 3.5V, IOUT = 0
VDD = 3.5V ~ 5V, IOUT = 0
--
Reset Threshold
VTH
TA = 27°C
--
Threshold Voltage Accuracy
∆VTH
TA = 27°C
--
VCC Drop to Reset Delay
tRD
Drop = -125mV
--
Reset Active Time Out Period
tRP
VDD ≥ 1.02×VTH,
Programmable
VIL
VSET Pin Input Threshold
RESET Output Voltage
DS9801-00 January 2002
3
3.3
Note1
µA
--
V
3
%
--
20
µS
--
200
--
mS
TA = 27°C
--
0.15VDD
--
VIH
TA = 27°C
--
0.85VDD
--
VOL
VDD < VTH, ISINK = 3.5mA
--
0.4
--
V
V
www.richtek-ic.com.tw
3
RT9801
Preliminary
Note 1: Pin Conditions for Programmable Threshold Voltage Setting
RT9801A
RT9801B
Vset0 input
Vset1 input
Vset2 input
5
4
VDD
VDD
VDD
4.9
3.9
VDD
VDD
floating
4.8
3.8
VDD
VDD
GND
4.7
3.7
VDD
floating
VDD
4.6
3.6
VDD
floating
floating
4.5
3.5
VDD
floating
GND
4.4
3.4
VDD
GND
VDD
4.3
3.3
VDD
GND
floating
4.2
3.2
VDD
GND
GND
4.1
3.1
floating
VDD
VDD
4
3
floating
VDD
floating
3.9
2.9
floating
VDD
GND
3.8
2.8
floating
floating
VDD
3.7
2.7
floating
floating
floating
3.6
2.6
floating
floating
GND
3.5
2.5
floating
GND
VDD
3.4
2.4
floating
GND
floating
3.3
2.3
floating
GND
GND
3.2
2.2
GND
VDD
VDD
3.1
2.1
GND
VDD
floating
3
2
GND
VDD
GND
2.9
1.9
GND
floating
VDD
2.8
1.8
GND
floating
floating
2.7
1.7
GND
floating
GND
2.6
1.6
GND
GND
VDD
2.5
1.5
GND
GND
floating
VDD: bond to VDD; 0: bond to GND; f: no bonding
www.richtek-ic.com.tw
4
DS9801-00 January 2002
RT9801
Preliminary
Package Information
D
C
B
b
H
A
A1
e
Symbol
L
Dimensions In Millimeters
Dimensions In Inches
Min
Max
Min
Max
A
0.889
1.295
0.035
0.051
A1
--
0.152
--
0.006
B
1.397
1.803
0.055
0.071
b
0.356
0.559
0.014
0.022
C
2.591
2.997
0.102
0.118
D
2.692
3.099
0.106
0.122
e
0.838
1.041
0.033
0.041
H
0.102
0.254
0.004
0.010
L
0.356
0.610
0.014
0.024
SOT- 26 Surface Mount Package
DS9801-00 January 2002
www.richtek-ic.com.tw
5
RT9801
Preliminary
RICHTEK TECHNOLOGY CORP.
RICHTEK TECHNOLOGY CORP.
Headquarter
Taipei Office (Marketing)
6F, No. 35, Hsintai Road, Chupei City
8F-1, No. 137, Lane 235, Paochiao Road, Hsintien City
Hsinchu, Taiwan, R.O.C.
Taipei County, Taiwan, R.O.C.
Tel: (8863)5510047 Fax: (8863)5537749
Tel: (8862)89191466 Fax: (8862)89191465
Email: [email protected]
www.richtek-ic.com.tw
6
DS9801-00 January 2002